Here's a patch to the util-linux package that enables readprofile o/p
instruction profiling. This also helps in determining spinlock contention
in a easy manner, (when CONFIG_FRAME_POINTER is enabled).
This patch is based on an old patch by Tridge for the same purpose.
Example commandline and o/p:
(Second column of the disassembly represents percentage)
# readprofile -m System.map-t -p profile.raw -v -v -k vmlinux-t -l 1000
.
.
0 __fput 0.0000
1139 fget 8.8984
31 2.72 ffffffff8017d890: sub $0x28,%rsp
9 0.79 ffffffff8017d894: mov %r12,0x18(%rsp)
1 0.09 ffffffff8017d899: mov %rbx,0x8(%rsp)
0 0.00 ffffffff8017d89e: mov %rbp,0x10(%rsp)
6 0.53 ffffffff8017d8a3: mov %r13,0x20(%rsp)
1 0.09 ffffffff8017d8a8: mov %edi,%r12d
0 0.00 ffffffff8017d8ab: mov %gs:0x0,%rax
76 6.67 ffffffff8017d8b4: mov 0x5d8(%rax),%rbx
255 22.39 ffffffff8017d8bb: xor %ebp,%ebp
0 0.00 ffffffff8017d8bd: lea 0x4(%rbx),%r13
11 0.97 ffffffff8017d8c1: mov %r13,%rdi
8 0.70 ffffffff8017d8c4: callq ffffffff8043fb40 <_spin_lock>
447 39.24 ffffffff8017d8c9: cmp 0x8(%rbx),%r12d
77 6.76 ffffffff8017d8cd: jae ffffffff8017d8da <fget+0x4a>
13 1.14 ffffffff8017d8cf: mov 0x18(%rbx),%rax
7 0.61 ffffffff8017d8d3: mov %r12d,%edx
0 0.00 ffffffff8017d8d6: mov (%rax,%rdx,8),%rbp
9 0.79 ffffffff8017d8da: test %rbp,%rbp
11 0.97 ffffffff8017d8dd: je ffffffff8017d8e3
<fget+0x53>
6 0.53 ffffffff8017d8df: lock incl 0x28(%rbp)
118 10.36 ffffffff8017d8e3: mov %r13,%rdi
4 0.35 ffffffff8017d8e6: callq ffffffff8043fb70
<_spin_unlock>
39 3.42 ffffffff8017d8eb: mov %rbp,%rax
6 0.53 ffffffff8017d8ee: mov 0x8(%rsp),%rbx
0 0.00 ffffffff8017d8f3: mov 0x18(%rsp),%r12
0 0.00 ffffffff8017d8f8: mov 0x10(%rsp),%rbp
4 0.35 ffffffff8017d8fd: mov 0x20(%rsp),%r13
0 0.00 ffffffff8017d902: add $0x28,%rsp
Thanks,
Kiran
Signed-off-by: Ravikiran Thirumalai <[email protected]>
--- util-linux-2.12p/sys-utils/readprofile.c 2004-12-11 05:41:09.000000000 +0530
+++ util-linux-2.12p-ppcfix/sys-utils/readprofile.c 2005-02-15 18:15:51.000000000 +0530
@@ -38,6 +38,9 @@
* 2003-08-12 Nikita Danilov <[email protected]>
* - added -s option; example of use:
* "readprofile -s -m /boot/System.map-test | grep __d_lookup | sort -n -k3"
+ * 2004-02-05 Ravikiran Thiumalai <[email protected]>
+ * - Added instruction profiling support; Use case:
+ * readprofile -m /boot/Sysytem.map-test -v -v -k /boot/vmlinux-test
*/
#include <errno.h>
@@ -58,7 +61,8 @@
/* These are the defaults */
static char defaultmap[]="/boot/System.map";
static char defaultpro[]="/proc/profile";
-static char optstring[]="M:m:np:itvarVbs";
+static char optstring[]="M:m:np:itvarVbsl:k:";
+static char *kernel_name="vmlinux";
static void *
xmalloc (size_t size) {
@@ -120,17 +124,68 @@
"\t -p <pro-file> (default: \"%s\")\n"
"\t -M <mult> set the profiling multiplier to <mult>\n"
"\t -i print only info about the sampling step\n"
- "\t -v print verbose data\n"
+ "\t -v print verbose data; -v -v for insn profile\n"
"\t -a print all symbols, even if count is 0\n"
"\t -b print individual histogram-bin counts\n"
"\t -s print individual counters within functions\n"
"\t -r reset all the counters (root only)\n"
"\t -n disable byte order auto-detection\n"
- "\t -V print version and exit\n"),
+ "\t -V print version and exit\n"
+ "\t -l <limit> set limit for disassembly\n"
+ "\t -k <kernel> set name of kernel image for disassembly\n"),
prgname, prgname, defaultmap, boot_uname_r_str(), defaultpro);
exit(1);
}
+static FILE *disass_start(char *kernel, unsigned long long start, int size)
+{
+ char cbuf[300];
+ FILE *p;
+ struct stat statbuf;
+ int i;
+
+ if (stat(kernel, &statbuf)) {
+ fprintf(stderr, "failed to stat %s\n", kernel);
+ return NULL;
+ }
+
+ sprintf(cbuf,
+ "objdump -d --no-show-raw-insn --start-address=0x%llx --stop-address=0x%llx %s",
+ start, start + size, kernel);
+ p = popen(cbuf, "r");
+ if (!p) {
+ printf("failed to run %s\n", cbuf);
+ return NULL;
+ }
+
+ /* Remove the top 6 lines of objdump blurb */
+ for (i = 1 ; i <= 6 ; i++)
+ if (!fgets(cbuf, sizeof(cbuf) - 1, p)) {
+ fprintf(stderr,
+ "objdump format incompatiblity or wrong kernel/mapfile combo\n");
+ pclose(p);
+ return NULL;
+ }
+ return p;
+}
+
+static char *disass_next(FILE *p)
+{
+ static char lbuf[200];
+
+ if (!fgets(lbuf, sizeof(lbuf) - 1, p))
+ return NULL;
+ if (strncmp(lbuf, "Disassembly", 11) == 0)
+ return NULL;
+
+ return lbuf;
+}
+
+static void disass_close(FILE *p)
+{
+ pclose(p);
+}
+
int
main(int argc, char **argv) {
FILE *map;
@@ -150,6 +205,7 @@
int maplineno=1;
int popenMap; /* flag to tell if popen() has been used */
int header_printed;
+ int dumplimit = 0;
#define next (current^1)
@@ -166,6 +222,9 @@
case 'm':
mapFile = optarg;
break;
+ case 'k':
+ kernel_name = optarg;
+ break;
case 'n':
optNative++;
break;
@@ -184,9 +243,12 @@
case 'i':
optInfo++;
break;
+ case 'l':
+ dumplimit = atoi(optarg);
+ break;
case 'M':
mult = optarg;
- break;
+
case 'r':
optReset++;
break;
@@ -324,6 +386,7 @@
*/
while (fgets(mapline,S_LEN,map)) {
unsigned int this=0;
+ unsigned index0 = indx, end_idx;
if (sscanf(mapline,"%llx %s %s",&next_add,mode,next_name)!=3) {
fprintf(stderr,_("%s: %s(%i): wrong map line\n"),
@@ -345,7 +408,8 @@
exit(1);
}
- while (indx < (next_add-add0)/step) {
+ end_idx = (next_add - add0) / step + 1; /* Since buf[0] is step */
+ while (indx < end_idx) {
if (optBins && (buf[indx] || optAll)) {
if (!header_printed) {
printf ("%s:\n", fn_name);
@@ -360,6 +424,45 @@
if (optBins) {
if (optVerbose || this > 0)
printf (" total\t\t\t\t%u\n", this);
+ } else if (optVerbose >= 2) {
+ fn_len = next_add - fn_add;
+ printf("%6i %-40s %8.4f\n", this, fn_name,
+ this / (double) fn_len);
+ if (this > dumplimit) {
+ FILE *p;
+ char *disass_nxt;
+ p = disass_start(kernel_name, fn_add,
+ ((end_idx - index0) * step));
+ if (!p)
+ exit(1);
+ /* read the first line..shudn't get NULL here */
+ disass_nxt = disass_next(p);
+ indx = index0;
+ while (disass_nxt) {
+ int smpls_insn;
+ char disass_cur[200];
+ unsigned long long disass_next_addr;
+ strncpy(disass_cur, disass_nxt, 200);
+ disass_nxt = disass_next(p);
+ smpls_insn = 0;
+ if (disass_nxt) {
+ sscanf(disass_nxt,"%llx",
+ &disass_next_addr);
+ while (add0+indx*step <
+ disass_next_addr)
+ smpls_insn += buf[indx++];
+ } else {
+ while (add0+indx*step <
+ next_add)
+ smpls_insn += buf[indx++];
+ }
+ printf("%d\t%8.2f\t%s", smpls_insn,
+ 100.0 * smpls_insn / this,
+ disass_cur);
+ }
+ disass_close(p);
+ indx = end_idx;
+ }
} else if ((this || optAll) &&
(fn_len = next_add-fn_add) != 0) {
if (optVerbose)